Underreamer



C. S. WRIGHT.

UNDERREAMER.

APPLICATION FILED APR. 20. 1920.

Patenta& Aug. 9, IZL

2 SHEETS-SHEET 1.

7////// K mm\ C, S; WEIGHT.

UNDERREAMER.

APPLICATION HLED APR.20. 1920.

patente& Aug. 9,1921.,

2 SHEETS-SHEET 2.

UNITED sTA s PATENT OFFICE;

CLYDE s. WEIGHT, or' TOLCEDO, 01510, ASSGNOR TO THE NATIONAL sunny. com- PA'NY, or rambo, OI-IIO, A CORPORATION OF OHIO.

UNDERREAMR.

Specification-f Letters ment.

Patented Aug. 9, 19211.

Application' med April 20, 1920. Serial No. 375373.

To all 'whom it may cancer-n:

Be it known that I CLYDE residing at Toledo, in the county of Lucas and State of- Ohio, have invented new and useful Im provements in Underreamers, of which the following is 'a' specification.

My invention relates toexpanding underreamers for enlarging the diameter of wells below the casing,

The object ofthis invention is to provide an underreamer with one bit or cutter integral 'with the body of the underreamer, the' other bit or cutter being collapsible by moving downwardly and inwardly or longitudi nally and transversely. Another object is to provide an expanding underreamer which may be employed also in drilling the well deeper like an ordinary solid bit. Another object is to prolong' the life of the tool as Compared with the life of the usual tool with two movable bits. Other objects appear hereinafter. a

Referring to the accompanying drawings, F igure 1 is a side elevation of an underreamer embodying my invention, the casing Shoe bein shown in vertical section and broken o ,-in this figure the parts of the tool are in drilling positions: Fig. 2 is a View similar to Fig. 1, but with the movable bits partlycollapsed; Fig. 3, a similar View, but with the movable bit fully collapsed;

i Fig. 4, an elevation of the tool body; Fig. 5,

an elevation of the tool body, the view being at right' angles to that' of Fg. 4; Fig. 6, a side elevation Ofgthe movable bit; Fig. 7, a

bottom plan View' of Fig. 1; Fig. 8, a bottom plan view of Fi 5; Fig. 9, a bottom plan view of Fig. 6; ig. 10, a top plan viewof Fig. 6; Fig. 11, a side view of the bitsuspending rod; and Fig. 12, a bottom plan View of Fg. 11. 4

On the drawings, 1' designates the' body of the underreamer, 2 the sub', 3 the'usual box-and-pin connectionsfor the body and the sub, and 4 the flats on the body'for the application of a wrench. The lower end of the bit 5, preferably integral with the body.

The bit 5 has its outer facerounded` tran;

versely on the are of a 'circle and extendin .BI outwardly beyond the face of the body. This outwardly inclined shoulder 6. The lower end of the bit has the outwardly extending reaming flange 7 connected to the bodyofg' the bit by the downwardly and outwardly" nclined shoulder 8. The lower end of the' bit may be shaped to suit the particular purposes, whether; of reaming or drilling or both.

The bit 5 is-provided with the longitudinal hole 9, here shown rectangular in crosssection, extending up to the body 1. The nner face 10 of the bit is provided with the slot 11 opening into the hole 9. The inner face 10, which is directly opposite the outer face of the bit, lies considerably within the downward continuation of the 'body and is preferably parallel with the axal center of the body. .The slot 11 terminates above at the horizontal shoulder 12 which may be considered the lower end of the body- 1. The slot 11 is somewhat narrower than the adjacent side of the hole, whereby the two longitudinal internal shoulders 13 are provided at the sides of the slot. The side walls 17 is an axial opening in the body 1. It

extends from the bottom of the pin-and-box connection 3 to thehole 9 and the slot 11, its upper part being enlarged to provide the seat 18- for the coiled spring. 19.

The movable bit 20 has its outer face shaped the same 'as the outer face of the bit 5, and has the flange 7 and the inclined shoulder 8 corresponding to the flange 7 and'iiclined shoulder 8 of the bit 5. It has the top inclined shoulder 6* corresponding j to'the shoulder 6 of the bit 5, but it is at a j 'body has the extension constitutingthe fixed lower position than the shoulder 5. The bit 20`in working position has its upper end seated on the shoulder '12 on the lower end ofthebody while the shoulder 6 is somealtgabove this end of the body. When in 'e working position the bit 20 has its outer the body 1, the shoulface extending beyond der 6 tapering up to the top of the bit 20 or to the bottom of the body 1. The bit 20 has the web 21 which extends through the slot 11 and has its inner edge provded with the double-flanged head 22 seated against the shoulders 13 when the bit is in expanded or working position. This head preferably engages the sides 23 of the hole 9 adgacent to the shoulders 13, but there is consderable space between the head and the opposte wall 24: of the hole 9 when the bt 20 s fully expanded, as shown in Fig. 7. i

On the rear face of the bit 20 and ad acent to the web 21 are the two shoulders 25 preferably parallel with the face 10 when the bit 20 is fully expanded or collapsed. The upper ends of these shoulders rest on the faces 26 and travel up or down the inclined faces 15 as the bit 20 is moved to the position shown in Fig. 1 from. that shown in Fig. 3, or to the position shown in Fig. 3 from that shown in Fig. 1.

The web 21 is provided with a vertical series of holes 27. Spreader blocks 28 are placed against the sides of the web 21 and the shoulders 25 and Secured to the web by the rivet 29 which is passed through the blocks, one at each side of the webs, and the lowest hole 27. Each block is as wide as the distance between the faces 10 and the shoulders 25 when the bit 20 is in working position, in which position the inner faces 30 of the blocks rest on the faces 10 to maintain the bit in its expanded or working position. The upper faces 37 of the blocks are inclined downwardly and inwardly so as to be parallel with the faces 15 when'the bit is expanded as in Fig. 1. The faces 26 and 30 have equal length, the faces 10 terminating at the lower ends of the faces 30, from which the bottom of the bit 5 is inclined downwardly and outwardly.

The upper end of the bit 20 has the slot 'i -31 open upwardly in the web 21 and the head 22. A hole 32 intersects the slot 31 and is elongated transversely. The suspension rod 33 has the flattened lower end 34 with the hole 35.

To assemble the underreamer, the end 34 of the rod 33 is placed in the slot 31 and the pin 35' is placed through the alined slot 32 and the hole 35, the length of the pin being the distance between the sides 23' of the hole 9. The free end of the rod is then inserted in the lower end of the hole 9, and the rod merma the bit 5, as shown in Fig. 3, and then put into the upper end of the well casing and pushed downwardly, the spring 19 causing the bits to engage the well-casng. As the inclined shoulder 6' passes below the casing the tool is moved laterally by the action of the bit 20 reacting' against the side of the well, the bit 20 moving upwardly under 'the action of the spring and outwardly under the action of the inclined shoulders 15 and 37 until the bit is in full working position as shown in Fig, 1.

When the tool is to be withdrawn from the well, an upward pull is exerted on the sub 2. The shoulder 6 first engages the lower end of the casing shoe 38, and moves the tool toward the bit 20. Soon the inclined shoulder 6 Contacts with the casing-shoe, which holds the bit 20 back while the remainder of the tool proceeds upwardly. When the tops of the shoulders 25 reach the inclined shoulders (at which time the tops of the faces 30 reach the bottom of the faces 10), the upper end of the bit 20 begins to move inwardly toward the bit 5 until the distance between the outer faces of the bits equals the internal diameter of the shoe 38.

Then the bits move up together. When the shoulder 8 engages the shoe the lower end of the bit 20 is swung inwardly and the bit' 20 retained, if necessary, until the bit is further moved inwardly to allow the flanges 8 and 8 to be moved into the shoe. Durin the lateral movement of the bits the slot 32 rides on the pin 35' without affecting the constant strain of the spring on the bit 20. As the bits become worn away the blocks 28 may be reset by removing the rivet 29 and securing them by a fresh rivet in the next hole 27 above the one from which the old rivet was taken.

The bit 5 may be used alone for drilling if desired. 4

ll claim:

1. lin an underreamer, a body, afixed underreaming bit carried thereby atits lower end, a complementary underreaming bit movable longitudinally and laterally from its working osition to its collapsed position, and ye dable means tending to move the movable bit toward its working position when displaced therefrom.

' 2. Tn an underreamer, a body, a fixed underreaming bit on the lower end of the body,

a complementary underreaming bit movable longitudinall and late'rally to its worln'ng and Collapse positions, a reciprocable rod seated in an opening in the body above the movable bit and suspending the movable bit, a spring surrounding the rod, and means causing the spring to exert a pull onthe rod tending to move the movable bit toward its working position when displ'aced therefrom.

3. Jin an underreamer, a body havin a longtudinal opening, a fixed unclerreamng bit on the lower end of the body, a complementary underreaming bit movable longitudinally and laterally to itsworking and collapsed positions, a rod reciprocable in the hollow body, means for moving the movable bit laterally -when it is moved longitudinally, a rod reciprocable in the longitudinal opening, a pin-and-slot connection between the rod and the movable bit, and a spring tending to move the rod and the movable bit to their working positions when displaced therefrom.

4. In an underreamer, a body having a longitudinal opening, a fixed underreamng bit having a longitudinal hole and a longitudinal slot communicating with the hole and the inner face of the bit, a complementary underreaming bit movable longitudinally and laterally and having a web in said slot and a head in said hole, the relative cross-sections of the head and the hole and width of the web permitting the movable bit to move transversely, means for moving the movable bit longitudnally, and means for causing the movable bit to move later-any away from the fixed bit when moved from collapsed ,to working position.

5. In an underreamer, abody having a longitudinal opening, a fixed underreaming bit having a-longitudinal hole and a longitudinal slot communicatin with the hole and the inner face of the bt, a complementary underreaming bit movable longitudinally and laterally and having a web in said slot and a head in said hole, the relative 'cross-sections of the head andthe hole and width of the web permitting the movable bit to move transversely, means for moving the movable bit longitudinally, and means for causing the movable bit to move laterally away from the fixed bit when moved from collapsed to working position, and permitting the movable bit to move laterally toward the fixed bit when moved from working position to collapsed position.

6. In an underreamer, a body, a fixed underreaming bit carried by the lower end of the body, a movable underreaming bit, a head-and-s1ot connection between the bits permitting longitudinal and limited transverse movement' of the movable bit', and a reciprocable spring actuated rod in the 'body having a pin-and-slot connection with the movable bit and tending to move the movable bit toward the body portion of the underreamer.

7. In an underreamer, a body, a fixed underreaming bit carried by the lower end of the body and having a longitudinal slot at its inner face, a movable bit having a web movable longitudinally and transversely in the slot, means carried by the web for controlling the transverse movements of the movable bit, and means for resetting the first means at a higher position on the web to compensate for the removal of portions of the lower end of the bit.

8. In an underreamer, a body, a fixed underreaming bit carried by the body, a longitudinally and transversely movable comple` mentary underreaming bit, means carried by the body for moving the movable bit longitudinally, and means controlling-the lat- 'eral movements of the lower end of the face, the web having a longtudinal series of openings, a cam-block on the web for controlling the lateral movements of the movable bit, and removable means passing through the cam-block and the lowest of said openings for securing the cam-block to the Web. V

Signed at Toledo', Ohio, this 12th day of April, 1920.'

y CLYDE s. WEIGHT. 

